Supplementation of grazing beef cattle with narasin

Gobato, Luiz Guilherme Mezzena; Polizel, Daniel Montanher; Júnior, Marcos Vinícius de Castro Ferraz; Miszura, Alexandre Arantes; Barroso, Juliana Machado; Martins, André S; Gonçalves, José Renato Silva; Ferreira, Evandro Maia; Pires, Alexandre Vaz

doi:10.1590/s1678-3921.pab2020.v55.01270

Cited by 2 publications

(1 citation statement)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Narasin is an ionophore approved by the Brazilian Ministry of Agriculture, Livestock, and Supply in 2015 (MAPA, 2020) for use as feed additive for ruminants. Since its approval, several studies have been conducted and demonstrated the positive effects of narasin on ruminal fermentation (Pasqualino et al, 2020;Polizel et al, 2020) and animal performance (Gobato et al, 2020;Polizel et al, 2021a). To our knowledge, the only studies that evaluated the use of narasin in lactating ewes demonstrated its potential to increase milk yield and efficiency when ewes were fed diets with ground corn as main energy source (Assis et al, 2020) or a mix of ground corn and citrus pulp (Sardinha et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

Narasin improves ewe milk yield efficiency and may affect performance of lambs

Martins

Polizel

Oliveira

et al. 2022

Sci. agric. (Piracicaba, Braz.)

Self Cite

View full text Add to dashboard Cite

Adding ionophores to ruminant diets is a strategy to manipulate ruminal fermentation and improve milk yield. This study evaluates the effects of narasin supply to lactating ewes on dry matter intake (DMI), milk yield and composition, and performance of the lambs. Thirty lactating Santa Inês and Santa Inês × Dorper ewes fed a basal diet containing 50 % coastcross hay and 50 % concentrate were randomly assigned to two treatments: control (CON; without ionophores) or NAR (addition of 13 mg narasin kg -1 DM). From the 2 nd to 10 th week of lactation, DMI of ewes was determined, and once a week, their milk production and composition was measured over a 3-h interval. At the 10 th week of lactation, lambs were weaned and their average daily gain (ADG) and starter DMI continued to be evaluated for two more weeks. Narasin supply did not affect weight and DMI of ewes. Ewes fed NAR had greater feed efficiency for milk production and displayed tendency for higher milk yield. Narasin supply reduced milk protein levels, but it did not affect other milk component levels. Ewes fed NAR had greater production of milk urea nitrogen and showed tendency for higher production of fat and total solids. Starter DMI of lambs was not affected by treatments; however, there was a tendency for greater weaning weight for NAR lambs. At the end of experiment, no differences were observed in the performance of lambs.The supply of 13 mg narasin kg -1 to lactating ewes improved milk yield efficiency and tended to increase the weaning weight of their lambs.

show abstract

Section: Introductionmentioning

confidence: 99%

Narasin improves ewe milk yield efficiency and may affect performance of lambs

Martins

Polizel

Oliveira

et al. 2022

Sci. agric. (Piracicaba, Braz.)

Self Cite

View full text Add to dashboard Cite

show abstract

Frequency of narasin intake affects ruminal metabolism and growth of lambs

et al. 2022

View full text Add to dashboard Cite

Context Ionophores improve rumen fermentation efficiency, average daily gain (ADG) and feed efficiency. However, the effects of providing ionophores to grazing animals are extremely variable, primarily due to infrequent supplement intake. Aim This study aimed to evaluate the effect of frequency of narasin intake on ruminal fermentation, nutrient digestibility and growth of lambs. Methods In Experiment I (metabolism assay), four rumen-cannulated wethers (1/2 Dorper × 1/2 Santa Inês) were assigned to a 4 × 4 Latin square design. The four treatments included a control, where animals were fed a diet without ionophore, and the following three treatments where animals were fed narasin at different intervals: 13 mg/kg of narasin every 24 h (N24), 26 mg/kg of narasin every 48 h (N48) and 39 mg/kg of narasin every 72 h (N72). All animals were fed with 95% Tifton-85 hay and 5% ground corn that was used as a vehicle for narasin. In Experiment II, 44 lambs (1/2 Dorper × 1/2 Santa Inês; 33.3 ± 0.5 kg (mean ± s.e.m.) and 180.5 ± 8 days of age) were used in a randomised complete-block design to assess performance. All treatments and management were similar to those in Experiment I. Key results Experiment I, dry-matter intake and apparent digestibility of nutrients were not affected by the treatments. The treatments N24 and N48 increased (P < 0.01) the total molar concentration of short-chain fatty acids compared with control and N72, and increased (P < 0.01) the concentration of propionate compared with control. In Experiment II, the treatments N24 and N48 increased the liveweight gain (P = 0.03) and feed efficiency (P = 0.02) compared with control and N72. Conclusion Effectiveness of narasin was reduced when offered at intervals greater than 48 h. Implication Frequency of narasin intake affects lamb production, and feeding systems are required where animals consume supplements on a regular basis.

show abstract

Supplementation of grazing beef cattle with narasin

Cited by 2 publications

References 21 publications

Narasin improves ewe milk yield efficiency and may affect performance of lambs

Narasin improves ewe milk yield efficiency and may affect performance of lambs

Frequency of narasin intake affects ruminal metabolism and growth of lambs

Contact Info

Product

Resources

About